This invention relates to metal foils and the like, and is more particularly directed to fabrication of sheets or ribbon formed of indium metal.
Indium is employed in a wide variety of applications because of its beneficial properties of slipperiness, soft cold ductility, ability to cold-weld to itself and wetability. Because indium is soft and easily worked over a wide range of temperatures including cryogenic and room temperature, it is often employed as a material for gaskets or glands. Indium gaskets perform well as mechanical or electrical seals. Indium, being soft and pliable, deforms into voids at the interface of parts to be joined where the gasket is fitted. Indium seals are often used in electronics equipment and are excellent for minimizing electromagnetic interference (EMI) and radio frequency interference (RFI).
On the other hand, flat sheets of indium are extremely flaccid, and this makes indium sheet foil, or ribbon material difficult to handle and inconvenient to employ. Indium is so soft that it will sag or flop when handled as a flat sheet or as a gasket preform. Also, indium is relatively expensive as compared with other metals such as copper.